This numeric entity is missing the final semicolon:
, that attribute value was closed by the subsequent tag
a
This document contains (do you see it?)
This document ends with That attribute value was bogus
The doctype is invalid because it contains extra whitespace
That boolean attribute had no value
Here's a nonexistent entity: &#foo; (do you see it?)
This document ends before the entity finishes: >

Paragraphs shouldn't contain block display elements, but this one does:

you see?

Multiple values for the same attribute.
Here's a table
This tag contains nothing but whitespace:

This p tag is cut off by

the end of the blockquote tag
Here's a nested table:
foo
This table contains bare markup
\n
This document contains a surprise doctype
Mixed case tags are folded to lowercase
Tag name contains Unicode characters
Attribute name contains Unicode characters
文本文件  |  35行  |  2.55 KB

A bare string
<!DOCTYPE xsl:stylesheet SYSTEM "htmlent.dtd">
<!DOCTYPE xsl:stylesheet PUBLIC "htmlent.dtd">
<div><![CDATA[A CDATA section where it doesn't belong]]></div>
<div><svg><![CDATA[HTML5 does allow CDATA sections in SVG]]></svg></div>
<div>A <meta> tag</div>
<div>A <br> tag that supposedly has contents.</br></div>
<div>AT&T</div>
<div><textarea>Within a textarea, markup like <b> tags and <&<&amp; should be treated as literal</textarea></div>
<div><script>if (i < 2) { alert("<b>Markup within script tags should be treated as literal.</b>"); }</script></div>
<div>This numeric entity is missing the final semicolon: <x t="pi&#241ata"></div>
<div><a href="http://example.com/</a> that attribute value never got closed</div>
<div><a href="foo</a>, </a><a href="bar">that attribute value was closed by the subsequent tag</a></div>
<! This document starts with a bogus declaration ><div>a</div>
<div>This document contains <!an incomplete declaration <div>(do you see it?)</div>
<div>This document ends with <!an incomplete declaration
<div><a style={height:21px;}>That attribute value was bogus</a></div>
<! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN">The doctype is invalid because it contains extra whitespace
<div><table><td nowrap>That boolean attribute had no value</td></table></div>
<div>Here's a nonexistent entity: &#foo; (do you see it?)</div>
<div>This document ends before the entity finishes: &gt
<div><p>Paragraphs shouldn't contain block display elements, but this one does: <dl><dt>you see?</dt></p>
<b b="20" a="1" b="10" a="2" a="3" a="4">Multiple values for the same attribute.</b>
<div><table><tr><td>Here's a table</td></tr></table></div>
<div><table id="1"><tr><td>Here's a nested table:<table id="2"><tr><td>foo</td></tr></table></td></div>
<div>This tag contains nothing but whitespace: <b>    </b></div>
<div><blockquote><p><b>This p tag is cut off by</blockquote></p>the end of the blockquote tag</div>
<div><table><div>This table contains bare markup</div></table></div>
<div><div id="1">\n <a href="link1">This link is never closed.\n</div>\n<div id="2">\n <div id="3">\n   <a href="link2">This link is closed.</a>\n  </div>\n</div></div>
<div>This document contains a <!DOCTYPE surprise>surprise doctype</div>
<div><a><B><Cd><EFG>Mixed case tags are folded to lowercase</efg></CD></b></A></div>
<div><our☃>Tag name contains Unicode characters</our☃></div>
<div><a ☃="snowman">Attribute name contains Unicode characters</a></div>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">